Pump jack



Dec. 2s, 1926. mimm- W. M, JENKINS PUMP JACK Filed May 27. i925 Patented Bec. 28, 1926.

'lvllvlqi STTES PUMP JACK.

Applcation led May 27, 1925.

rlhis invention relates to driving mechanism tor pumps commonly known as pump jacks, and especially to that type or' pump j aclts employing a reciprocating lever driven from a rotary gear.

lt is an object ot the invention to provide an extremely simple but highly efficient pump jack comprising a minimum number ol parts and of exceptionally strong and durable construction. l

lt is an additional object to provide a pump j acl; having a reciprocating lever, which lever is driven in its lifting stroke at slower speed and with a greater transmission ot power than in its downward stroke, thereby speeding up the action of the pump and giving the greatest power where it is needed in lifting the water.

Another object ot the invention is to provide a pivoted reciprocating lever having secured thereto an arcuate or concavo conver internal gear engaged by a pinion rotating on a lined axis, the concave and convex sides ot' sair gear being disposed substan* tially concentric with the pivot point of said lever.

A still further object is in such a device to provide means in the form oi3 a cam guideway concentric with the concave convex internal gear for properly guiding the gear in its traveling movement about the driving pinion, holding` said parts in proper engagement at all times.

Ain additional object of the invention is to provide in such a pump jaclt a closed casing 'for all the worlnng parts in which an oil receptacle is provided adapted to supply oil through the movement of the reciprocating lever to all of' said parts.

Another object of the invention is to provide a reciprocating lever slidahly pivoted adjacent one end thereof and carrying a concavo convex internal gear rigidly securedadjacent the other end, in mesh with a pinion rotating on a fixed axis, the slidable pivot. of said lever permitting the ends of said gear to be moved around said pinion, whereby said pinion may engage the opposite side of said gear, and, in such a slidable pivotal connection, to provide means for varying the normal pivot point of the lever whereby the length ot the stroke of said lever may he considerably varied.

These and other lobjects may lie-.apparent from the following description made in connection with the accompanying drawings,

Serial No. 33,168.

wherein like characters refer to like parts throughout the several views, and, in which.

Fig. 1 is a side elevation ot the pump jacl, some portions oi" the casing being broken away, and others shown in section;

Fig. 2 is a horizontal cross section oit the same taken on the line 22 ot' Fig. l;

Fig. 3 is a diagonal cross section taken on the line 8-3 of Fig. l; and

Fig. l is a vertical cross section talten on two shell sections 5 and 6 are also provided with outwardly projecting` flanges 5b and 6b,

respectively, which are bolted together to form the closed casing. `The lower portion of the casing adjacent the basetorms a receptacle 8 adapted to contain oil tor the lubrication ot the working parts of the jaclr. A vertical slot 9 is formed in the front wall or' the casing, through which the working end of a reciprocating'lever l() is adapted to be swung. The lever 10 is provided at its inner end with a bearing slot 10a. Oppositely aligned adjustment slots 11 are termed in the sides of sections 5 and 6, respectively, and a nutted bolt l2 is passed through said adjustment slots 1l through the bearing slot 10a of the lever, thereby .slidahly pivotingl said lever to the casing. The. holt may thus he rigidly clamped in a desired transverse position in slots 11, thereby determining the pivotk point of lever 10. bviously, this pivot point may be varied by the position ot holt l2 in slots ll from the outside ot the casing. Bossesll are projected on the inner sides of sections 5 and 6 ot the casing in hori- Zontal alignment, and adapted to Itorni bearing surfaces for the pivoted end or" lever l0. A hearing 13 is provided in the section 5 ot the casing adjacent the 'front end thereof;

and substantiallv in horizontal alignment with the adjus nt slots 1l, and a transverse 'shaft 14tis joui-nailed in hearing 13` carrying outside the casingthe pulleyrl con-4 nected by an endless belt 16 to a motor or other source of power 17. On the inner end of shaft lll, a relativelysmall pinion 18 is keyed or otherwise rigidly secured, prefer# ably being disposed centrally and longitudinally of the casino'. It will be noticed that the inner end 14'L1 of shaft 14 is extended somewhat beyond the pinion 18, the purpose of which will presently be explained.

The lever 10 has a relatively large, pref erably elliptical shaped head or plate portion 1()b vertically disposed adjacentA its outer end and the front end of the casing. Rigidly secured to the enlarged head 10b of the reciprocating lever, is a concavo convex orareuate internal gear 19 having its concave and convex sides disposed substantially concentric with the normal pivot point of lever 10. A concavo convex shaped flange 19a, corresponding with the gear 19, is secured to the outer surface of said gear and engages the outer side of the pinion 18, thereby holding gear 19 'to said pinion. A guideway or cam 20, also of concave convex shape. is formed in the enlarged head 10b, extending within and concentric to the gear 19. Pinion 18 is disposed within the sides of gear 19 engaging the same, and the' projecting end le of the rotary shaft 14 is seated in the cam or guide 20, thereby maintaining the propel` enga-gement between pinion 18 and gear 19 at all times during the movement of the latter. Outturned arms 21 are rigidly secured to the free end of lever 10 on the outer side of the slot 9. A pair of pitmen 22 are pivoted to said arms adapted to actuate the pump piston through the reciprocation of lever 10. A transverse outwardly extending colla-r 23 is formed on the lever 10 between the enlarged head 10b and the outer end of the said lever adjacent the inner side of slot 9, which collar is adapted to prevent oil fromrunningy down lever 10 and outof the casingthrough slot 9. The collar 23 thus catches any oil traveling down the lever and drops the same back in receptacle portion 8 of the casing. A. gasket 24 is interposed between the two lower portions of the sections 5 and @,when the same are secured together, thereby making a liquid tight joint in thereceptacle part of the casing.

Operation- Assuming the pitmen 22 to be directly connectedto the piston of the pump,

when a clockwise rotation is transmittedto the shaft 1li, the pinion 18 will cause the gear to move therearoundl in an arcuate concavo convex path, thereby reciprocating lever 10. lt will be obvious that, in the upstroke or lifting stroke of lever 10, the concave or longer side of gear 19 will be engaged, said side of said gear being of greater radius than the convex or short-er side. Consequently, a greater gear reduction will exist when saidV concave side of the gear is engaged, thereby giving the lifting stroke of the lever greater power and less speed than the down stroke. Increased power is, therefore, provided in the lifting stroke where it is most needed, while the plunger of the pump will be reciprocated downwardly at faster speed where little power is needed.

By unloosening the nut on bolt 12 and rigidly setting it to a desired transverse position in the slots 11, the radius of the reciprocating lever 10 may obviously be vari-ec and the stroke of the lever consetpuentlyv changed within certain limits. Obviously, this adjustment may be made from the outside of the casing, either when the device is idle or when the device' is in operation. The length of slots'ltla and 11, of course, determine the limitation of 'this adjustment in the length of the stroke of the lever.

lt will be noticed that the lower end of the enlarged head1()b carrying the arcuate internal gear, at each down stroke of the lever, is immersed in the oil carried in receptacle 8 of the casing, and that small amounts of this oil will be carried to the pinion on .each 11p-stroke of the lever land will also run down the main portion ofthe lever 10 to the pivot bolt 12 and the slide bearing 10, thereby lubricating all-working parts of the device. As has been stated, the oilwill be prevented from ruiming down the outer end of the lever and out of the casing by means or" the outwardly extending collar 23.

From the above description, it will be seen that applicant has invented a pump jack comprising very few parts, but operating efficiently for all purposes intended. The device has been put to actual usage and has been found highly successful for the purposes enumerated.

In severalStates, laws have been enacted requiring all working machinery to be covered or have the moving parts thereofguarded or covered for the protection of the'public. Applicants device provides a pinnpjacl: having all of its working parts housed within a casing, and thereby complying' with the laws of these States.

lt will, of course, be understood that various changes may be made in theform, details, proportion and arrangement of parts without departing from/the scopeof the invention.

What is claimedVY is LA. pump jack having in combination a frame having spaced sides, a lever ,or walking beam mounted within said frame. and having its inner end slidably pivoted to the sides of said frame, a. concavo-conveX gear rigidly carried at one side of said'lever, a pinion journaledV in one side of said frame. and engaging said gear to oscillate said lever, means connected to said pinion and co-operating means carried by said gear adapted to maintainv the engagement between these parts, an-d means for connecting said lever with a pump plunger.

2.' A pump jack'having incombination an upright casing, having a` substantially ver'- tical slot in one edgeu thereof, a: lever or gear rigidly carried at one side of said lever,

a pinion journaled in said casing and engaging said gear to oscillate said lever, means for aording said gear horizontal motion relative to said pinion, means for maintaining the engagement between said pinion and gear, and means Jfor connecting the 'free end Iof said lever with a pump plunger.

3. A pump jack having in combination an upright casing, a walking beam pivoted 7ithin said casing and having its free end working through said casing, a concavo-con veX internal gear rigidly carried at one side of said lever, a horizontally disposed .stub shaft journaled in one side of said casing adjacent said gear, a pinion rigidly secured to said stub shaft within said casing engaging said gear, a guide adjacent said gear in which the inwardly projecting end 4of said stub shaft is seated, adapted to maintain the engag-ement of said gear and pinion and means for connecting said lever with a pump plunger.

1l. A pump jack having in combination a frame having a bearing slot therein, a lever having a bearing slot adjacent one end thereof, an adjustable pivot member passing through said slot in said lever and adapted to be secured to said frame in various positions relative to said slot in said frame, a concavo convex gear mounted on said lever, a pinion journaled in said frame engaging said gear, and means for maintaining the engagement of said gear and pinion.

5. A pump jack having in combination an upright hollow easing or frame having a vertical slot through one end thereof,l a lever pivoted within said casing and having its free end working through said slot, a driving shaft journaled in said casing, a pinion rigidly secured to the inner end of said shaft within sai-d casing, and a. gear on said lever engaging said pinion operative to reciprocate said lever when said 'shaft is rotated, the lower portion of said casing constituting a receptacle adapted to contain a lubricating luid, whereby said gear will be immersed into said fluid when said lever Y is reciprocated and said pinion and pivot of said lever will be subsequently lubricated.

6. The .structure set forth in claim 5, and said lever having a flange on the outer side of said gear adapted to prevent lubricating fluid from Vflowing down said lever to thc outer side of said casing.

7. A pump jaclr having in combination a hollow casing having a slot through one end thereof, a lever disposed for the most part within said casing and slidably pivoted thereto but having one or its ends working through said slot, a concavo convex internal gear rigidly carrie-d by said lever and disposed within said casing, a transverse hori- Zontal shaft journalled in sai-d Casing, a pinion rigidly carried by the inner end of said shaft and engaging said gear, projecting means carried by said shaft in alignment therewith and aguideway concentric with said gear. in which said projecting means is seated, whereby said pinion will be held in engagement with said gear and said lever will be reciprocated when said shaft is continuously turned in one direction.

8. The structure set forth in claim 7, and said hollow casing having its inner lower portion in the form 01' a receptacle adapted to contain oil whereby said gear, pinion and pivot member of said lever may be oiled when said lever is reciprocated.

In testimony whereof I affix my signature.

,lv/WILLIAM M. JENKINS. 

